Articles | Volume 6, issue 1
https://doi.org/10.5194/tc-6-221-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/tc-6-221-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
17 Feb 2012
Research article |
| 17 Feb 2012
Derivation and analysis of a high-resolution estimate of global permafrost zonation
S. Gruber
Glaciology, Geomorphodynamics and Geochronology, Department of Geography, University of Zurich, Switzerland
Related subject area
Frozen Ground
Significant underestimation of peatland permafrost along the Labrador Sea coastline in northern Canada
Estimation of stream water components and residence time in a permafrost catchment in the central Tibetan Plateau using long-term water stable isotopic data
The temperature-dependent shear strength of ice-filled joints in rock mass considering the effect of joint roughness, opening and shear rates
Brief communication: Improving ERA5-Land soil temperature in permafrost regions using an optimized multi-layer snow scheme
Towards accurate quantification of ice content in permafrost of the Central Andes – Part 2: An upscaling strategy of geophysical measurements to the catchment scale at two study sites
Long-term analysis of cryoseismic events and associated ground thermal stress in Adventdalen, Svalbard
Seismic physics-based characterization of permafrost sites using surface waves
Three in one: GPS-IR measurements of ground surface elevation changes, soil moisture, and snow depth at a permafrost site in the northeastern Qinghai–Tibet Plateau
Surface temperatures and their influence on the permafrost thermal regime in high-Arctic rock walls on Svalbard
Consequences of permafrost degradation for Arctic infrastructure – bridging the model gap between regional and engineering scales
Passive seismic recording of cryoseisms in Adventdalen, Svalbard
Projecting circum-Arctic excess-ground-ice melt with a sub-grid representation in the Community Land Model
Ground ice, organic carbon and soluble cations in tundra permafrost soils and sediments near a Laurentide ice divide in the Slave Geological Province, Northwest Territories, Canada
The ERA5-Land soil temperature bias in permafrost regions
Brief Communication: The reliability of gas extraction techniques for analysing CH4 and N2O compositions in gas trapped in permafrost ice wedges
Geochemical signatures of pingo ice and its origin in Grøndalen, west Spitsbergen
Mountain permafrost degradation documented through a network of permanent electrical resistivity tomography sites
Permafrost variability over the Northern Hemisphere based on the MERRA-2 reanalysis
Distinguishing ice-rich and ice-poor permafrost to map ground temperatures and ground ice occurrence in the Swiss Alps
New ground ice maps for Canada using a paleogeographic modelling approach
Origin, burial and preservation of late Pleistocene-age glacier ice in Arctic permafrost (Bylot Island, NU, Canada)
Characteristics and fate of isolated permafrost patches in coastal Labrador, Canada
Rock glaciers in Daxue Shan, south-eastern Tibetan Plateau: an inventory, their distribution, and their environmental controls
Microtopographic control on the ground thermal regime in ice wedge polygons
Change in frozen soils and its effect on regional hydrology, upper Heihe basin, northeastern Qinghai–Tibetan Plateau
Climate warming over the past half century has led to thermal degradation of permafrost on the Qinghai–Tibet Plateau
Decadal changes of surface elevation over permafrost area estimated using reflected GPS signals
Characterizing permafrost active layer dynamics and sensitivity to landscape spatial heterogeneity in Alaska
Resolution capacity of geophysical monitoring regarding permafrost degradation induced by hydrological processes
A new map of permafrost distribution on the Tibetan Plateau
Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ2H analysis
Modelling rock wall permafrost degradation in the Mont Blanc massif from the LIA to the end of the 21st century
New observations indicate the possible presence of permafrost in North Africa (Djebel Toubkal, High Atlas, Morocco)
Transient modeling of the ground thermal conditions using satellite data in the Lena River delta, Siberia
Wind-driven snow conditions control the occurrence of contemporary marginal mountain permafrost in the Chic-Choc Mountains, south-eastern Canada: a case study from Mont Jacques-Cartier
Numerical modelling of convective heat transport by air flow in permafrost talus slopes
Cryostratigraphy, sedimentology, and the late Quaternary evolution of the Zackenberg River delta, northeast Greenland
Response of seasonal soil freeze depth to climate change across China
Soil moisture redistribution and its effect on inter-annual active layer temperature and thickness variations in a dry loess terrace in Adventdalen, Svalbard
Review article: Inferring permafrost and permafrost thaw in the mountains of the Hindu Kush Himalaya region
Strong degradation of palsas and peat plateaus in northern Norway during the last 60Â years
Weichselian permafrost depth in the Netherlands: a comprehensive uncertainty and sensitivity analysis
Semi-automated calibration method for modelling of mountain permafrost evolution in Switzerland
Presence of rapidly degrading permafrost plateaus in south-central Alaska
Modeling the spatiotemporal variability in subsurface thermal regimes across a low-relief polygonal tundra landscape
Thermal impacts of engineering activities and vegetation layer on permafrost in different alpine ecosystems of the Qinghai–Tibet Plateau, China
Effects of stratified active layers on high-altitude permafrost warming: a case study on the Qinghai–Tibet Plateau
Coastal dynamics and submarine permafrost in shallow water of the central Laptev Sea, East Siberia
Diagnostic and model dependent uncertainty of simulated Tibetan permafrost area
Simulated high-latitude soil thermal dynamics during the past 4 decades
Yifeng Wang, Robert G. Way, Jordan Beer, Anika Forget, Rosamond Tutton, and Meredith C. Purcell
The Cryosphere, 17, 63–78, https://doi.org/10.5194/tc-17-63-2023, https://doi.org/10.5194/tc-17-63-2023, 2023
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Peatland permafrost in northeastern Canada has been misrepresented by models, leading to significant underestimates of peatland permafrost and permafrost distribution along the Labrador Sea coastline. Our multi-stage, multi-mapper, consensus-based inventorying process, supported by field- and imagery-based validation efforts, identifies peatland permafrost complexes all along the coast. The highest density of complexes is found to the south of the current sporadic discontinuous permafrost limit.
Shaoyong Wang, Xiaobo He, Shichang Kang, Hui Fu, and Xiaofeng Hong
The Cryosphere, 16, 5023–5040, https://doi.org/10.5194/tc-16-5023-2022, https://doi.org/10.5194/tc-16-5023-2022, 2022
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This study used the sine-wave exponential model and long-term water stable isotopic data to estimate water mean residence time (MRT) and its influencing factors in a high-altitude permafrost catchment (5300 m a.s.l.) in the central Tibetan Plateau (TP). MRT for stream and supra-permafrost water was estimated at 100 and 255 d, respectively. Climate and vegetation factors affected the MRT of stream and supra-permafrost water mainly by changing the thickness of the permafrost active layer.
Shibing Huang, Haowei Cai, Zekun Xin, and Gang Liu
The Cryosphere Discuss., https://doi.org/10.5194/tc-2022-155, https://doi.org/10.5194/tc-2022-155, 2022
Revised manuscript accepted for TC
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1. The warming degradation mechanism of ice-filled joints were revealed. 2. The effect of temperature, normal stress, shear rate and joint opening on the shear strength of rough ice-filled joints were comprehensively investigated. 3. The shear rupture modes include shear cracking of joint ice and debonding of ice-rock interface, which is related with the above factors. 4. The bonding strength of ice-rock interface is larger than the shear strength of joint ice when the temperature is below -1°C.
Bin Cao, Gabriele Arduini, and Ervin Zsoter
The Cryosphere, 16, 2701–2708, https://doi.org/10.5194/tc-16-2701-2022, https://doi.org/10.5194/tc-16-2701-2022, 2022
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We implemented a new multi-layer snow scheme in the land surface scheme of ERA5-Land with revised snow densification parameterizations. The revised HTESSEL improved the representation of soil temperature in permafrost regions compared to ERA5-Land; in particular, warm bias in winter was significantly reduced, and the resulting modeled near-surface permafrost extent was improved.
Tamara Mathys, Christin Hilbich, Lukas U. Arenson, Pablo A. Wainstein, and Christian Hauck
The Cryosphere, 16, 2595–2615, https://doi.org/10.5194/tc-16-2595-2022, https://doi.org/10.5194/tc-16-2595-2022, 2022
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With ongoing climate change, there is a pressing need to understand how much water is stored as ground ice in permafrost. Still, field-based data on permafrost in the Andes are scarce, resulting in large uncertainties regarding ground ice volumes and their hydrological role. We introduce an upscaling methodology of geophysical-based ground ice quantifications at the catchment scale. Our results indicate that substantial ground ice volumes may also be present in areas without rock glaciers.
Rowan Romeyn, Alfred Hanssen, and Andreas Köhler
The Cryosphere, 16, 2025–2050, https://doi.org/10.5194/tc-16-2025-2022, https://doi.org/10.5194/tc-16-2025-2022, 2022
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We have investigated a long-term record of ground vibrations, recorded by a seismic array installed in Adventdalen, Svalbard. This record contains a large number of
frost quakes, a type of ground shaking that can be produced by cracks that form as the ground cools rapidly. We use underground temperatures measured in a nearby borehole to model forces of thermal expansion and contraction that can cause these cracks. We also use the seismic measurements to estimate where these cracks occurred.
Hongwei Liu, Pooneh Maghoul, and Ahmed Shalaby
The Cryosphere, 16, 1157–1180, https://doi.org/10.5194/tc-16-1157-2022, https://doi.org/10.5194/tc-16-1157-2022, 2022
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The knowledge of physical and mechanical properties of permafrost and its location is critical for the management of permafrost-related geohazards. Here, we developed a hybrid inverse and multiphase poromechanical approach to quantitatively estimate the physical and mechanical properties of a permafrost site. Our study demonstrates the potential of surface wave techniques coupled with our proposed data-processing algorithm to characterize a permafrost site more accurately.
Jiahua Zhang, Lin Liu, Lei Su, and Tao Che
The Cryosphere, 15, 3021–3033, https://doi.org/10.5194/tc-15-3021-2021, https://doi.org/10.5194/tc-15-3021-2021, 2021
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We improve the commonly used GPS-IR algorithm for estimating surface soil moisture in permafrost areas, which does not consider the bias introduced by seasonal surface vertical movement. We propose a three-in-one framework to integrate the GPS-IR observations of surface elevation changes, soil moisture, and snow depth at one site and illustrate it by using a GPS site in the Qinghai–Tibet Plateau. This study is the first to use GPS-IR to measure environmental variables in the Tibetan Plateau.
Juditha Undine Schmidt, Bernd Etzelmüller, Thomas Vikhamar Schuler, Florence Magnin, Julia Boike, Moritz Langer, and Sebastian Westermann
The Cryosphere, 15, 2491–2509, https://doi.org/10.5194/tc-15-2491-2021, https://doi.org/10.5194/tc-15-2491-2021, 2021
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This study presents rock surface temperatures (RSTs) of steep high-Arctic rock walls on Svalbard from 2016 to 2020. The field data show that coastal cliffs are characterized by warmer RSTs than inland locations during winter seasons. By running model simulations, we analyze factors leading to that effect, calculate the surface energy balance and simulate different future scenarios. Both field data and model results can contribute to a further understanding of RST in high-Arctic rock walls.
Thomas Schneider von Deimling, Hanna Lee, Thomas Ingeman-Nielsen, Sebastian Westermann, Vladimir Romanovsky, Scott Lamoureux, Donald A. Walker, Sarah Chadburn, Erin Trochim, Lei Cai, Jan Nitzbon, Stephan Jacobi, and Moritz Langer
The Cryosphere, 15, 2451–2471, https://doi.org/10.5194/tc-15-2451-2021, https://doi.org/10.5194/tc-15-2451-2021, 2021
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Climate warming puts infrastructure built on permafrost at risk of failure. There is a growing need for appropriate model-based risk assessments. Here we present a modelling study and show an exemplary case of how a gravel road in a cold permafrost environment in Alaska might suffer from degrading permafrost under a scenario of intense climate warming. We use this case study to discuss the broader-scale applicability of our model for simulating future Arctic infrastructure failure.
Rowan Romeyn, Alfred Hanssen, Bent Ole Ruud, Helene Meling Stemland, and Tor Arne Johansen
The Cryosphere, 15, 283–302, https://doi.org/10.5194/tc-15-283-2021, https://doi.org/10.5194/tc-15-283-2021, 2021
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A series of unusual ground motion signatures were identified in geophone recordings at a frost polygon site in Adventdalen on Svalbard. By analysing where the ground motion originated in time and space, we are able to classify them as cryoseisms, also known as frost quakes, a ground-cracking phenomenon that occurs as a result of freezing processes. The waves travelling through the ground produced by these frost quakes also allow us to measure the structure of the permafrost in the near surface.
Lei Cai, Hanna Lee, Kjetil Schanke Aas, and Sebastian Westermann
The Cryosphere, 14, 4611–4626, https://doi.org/10.5194/tc-14-4611-2020, https://doi.org/10.5194/tc-14-4611-2020, 2020
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A sub-grid representation of excess ground ice in the Community Land Model (CLM) is developed as novel progress in modeling permafrost thaw and its impacts under the warming climate. The modeled permafrost degradation with sub-grid excess ice follows the pathway that continuous permafrost transforms into discontinuous permafrost before it disappears, including surface subsidence and talik formation, which are highly permafrost-relevant landscape changes excluded from most land models.
Rupesh Subedi, Steven V. Kokelj, and Stephan Gruber
The Cryosphere, 14, 4341–4364, https://doi.org/10.5194/tc-14-4341-2020, https://doi.org/10.5194/tc-14-4341-2020, 2020
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Permafrost beneath tundra near Lac de Gras (Northwest Territories, Canada) contains more ice and less organic carbon than shown in global compilations. Excess-ice content of 20–60 %, likely remnant Laurentide basal ice, is found in upland till. This study is based on 24 boreholes up to 10 m deep. Findings highlight geology and glacial legacy as determinants of a mosaic of permafrost characteristics with potential for thaw subsidence up to several metres in some locations.
Bin Cao, Stephan Gruber, Donghai Zheng, and Xin Li
The Cryosphere, 14, 2581–2595, https://doi.org/10.5194/tc-14-2581-2020, https://doi.org/10.5194/tc-14-2581-2020, 2020
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This study reports that ERA5-Land (ERA5L) soil temperature bias in permafrost regions correlates with the bias in air temperature and with maximum snow height. While global reanalyses are important drivers for permafrost study, ERA5L soil data are not well suited for directly informing permafrost research decision making due to their warm bias in winter. To address this, future soil temperature products in reanalyses will require permafrost-specific alterations to their land surface models.
Ji-Woong Yang, Jinho Ahn, Go Iwahana, Sangyoung Han, Kyungmin Kim, and Alexander Fedorov
The Cryosphere, 14, 1311–1324, https://doi.org/10.5194/tc-14-1311-2020, https://doi.org/10.5194/tc-14-1311-2020, 2020
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Thawing permafrost may lead to decomposition of soil carbon and nitrogen and emission of greenhouse gases. Thus, methane and nitrous oxide compositions in ground ice may provide information on their production mechanisms in permafrost. We test conventional wet and dry extraction methods. We find that both methods extract gas from the easily extractable parts of the ice and yield similar results for mixing ratios. However, both techniques are unable to fully extract gas from the ice.
Nikita Demidov, Sebastian Wetterich, Sergey Verkulich, Aleksey Ekaykin, Hanno Meyer, Mikhail Anisimov, Lutz Schirrmeister, Vasily Demidov, and Andrew J. Hodson
The Cryosphere, 13, 3155–3169, https://doi.org/10.5194/tc-13-3155-2019, https://doi.org/10.5194/tc-13-3155-2019, 2019
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As Norwegian geologist Liestøl (1996) recognised,
in connection with formation of pingos there are a great many unsolved questions. Drillings and temperature measurements through the pingo mound and also through the surrounding permafrost are needed before the problems can be better understood. To shed light on pingo formation here we present the results of first drilling of pingo on Spitsbergen together with results of detailed hydrochemical and stable-isotope studies of massive-ice samples.
Coline Mollaret, Christin Hilbich, Cécile Pellet, Adrian Flores-Orozco, Reynald Delaloye, and Christian Hauck
The Cryosphere, 13, 2557–2578, https://doi.org/10.5194/tc-13-2557-2019, https://doi.org/10.5194/tc-13-2557-2019, 2019
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We present a long-term multisite electrical resistivity tomography monitoring network (more than 1000 datasets recorded from six mountain permafrost sites). Despite harsh and remote measurement conditions, the datasets are of good quality and show consistent spatio-temporal variations yielding significant added value to point-scale borehole information. Observed long-term trends are similar for all permafrost sites, showing ongoing permafrost thaw and ground ice loss due to climatic conditions.
Jing Tao, Randal D. Koster, Rolf H. Reichle, Barton A. Forman, Yuan Xue, Richard H. Chen, and Mahta Moghaddam
The Cryosphere, 13, 2087–2110, https://doi.org/10.5194/tc-13-2087-2019, https://doi.org/10.5194/tc-13-2087-2019, 2019
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The active layer thickness (ALT) in middle-to-high northern latitudes from 1980 to 2017 was produced at 81 km2 resolution by a global land surface model (NASA's CLSM) with forcing fields from a reanalysis data set, MERRA-2. The simulated permafrost distribution and ALTs agree reasonably well with an observation-based map and in situ measurements, respectively. The accumulated above-freezing air temperature and maximum snow water equivalent explain most of the year-to-year variability of ALT.
Robert Kenner, Jeannette Noetzli, Martin Hoelzle, Hugo Raetzo, and Marcia Phillips
The Cryosphere, 13, 1925–1941, https://doi.org/10.5194/tc-13-1925-2019, https://doi.org/10.5194/tc-13-1925-2019, 2019
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A new permafrost mapping method distinguishes between ice-poor and ice-rich permafrost. The approach was tested for the entire Swiss Alps and highlights the dominating influence of the factors elevation and solar radiation on the distribution of ice-poor permafrost. Our method enabled the indication of mean annual ground temperatures and the cartographic representation of permafrost-free belts, which are bounded above by ice-poor permafrost and below by permafrost-containing excess ice.
H. Brendan O'Neill, Stephen A. Wolfe, and Caroline Duchesne
The Cryosphere, 13, 753–773, https://doi.org/10.5194/tc-13-753-2019, https://doi.org/10.5194/tc-13-753-2019, 2019
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In this paper, we present new models to depict ground ice in permafrost in Canada, incorporating knowledge from recent studies. The model outputs we present reproduce observed regional ground ice conditions and are generally comparable with previous mapping. However, our results are more detailed and more accurately reflect ground ice conditions in many regions. The new mapping is an important step toward understanding terrain response to permafrost degradation in Canada.
Stephanie Coulombe, Daniel Fortier, Denis Lacelle, Mikhail Kanevskiy, and Yuri Shur
The Cryosphere, 13, 97–111, https://doi.org/10.5194/tc-13-97-2019, https://doi.org/10.5194/tc-13-97-2019, 2019
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This study provides a detailed description of relict glacier ice preserved in the permafrost of Bylot Island (Nunavut). We demonstrate that the 18O composition (-34.0 0.4 ‰) of the ice is consistent with the late Pleistocene age ice in the Barnes Ice Cap. As most of the glaciated Arctic landscapes are still strongly determined by their glacial legacy, the melting of these large ice bodies could have significant impacts on permafrost geosystem landscape dynamics and ecosystems.
Robert G. Way, Antoni G. Lewkowicz, and Yu Zhang
The Cryosphere, 12, 2667–2688, https://doi.org/10.5194/tc-12-2667-2018, https://doi.org/10.5194/tc-12-2667-2018, 2018
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Isolated patches of permafrost in southeast Labrador are among the southernmost lowland permafrost features in Canada. Local characteristics at six sites were investigated from Cartwright, NL (~ 54° N) to Blanc-Sablon, QC (~ 51° N). Annual ground temperatures varied from −0.7 °C to −2.3 °C with permafrost thicknesses of 1.7–12 m. Ground temperatures modelled for two sites showed permafrost disappearing at the southern site by 2060 and persistence beyond 2100 at the northern site only for RCP2.6.
Zeze Ran and Gengnian Liu
The Cryosphere, 12, 2327–2340, https://doi.org/10.5194/tc-12-2327-2018, https://doi.org/10.5194/tc-12-2327-2018, 2018
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This article provides the first rock glacier inventory of Daxue Shan, south- eastern Tibetan Plateau. This study provides important data for exploring the relation between maritime periglacial environments and the development of rock glaciers on the south-eastern Tibetan Plateau (TP). It may also highlight the characteristics typical of rock glaciers found in a maritime setting.
Charles J. Abolt, Michael H. Young, Adam L. Atchley, and Dylan R. Harp
The Cryosphere, 12, 1957–1968, https://doi.org/10.5194/tc-12-1957-2018, https://doi.org/10.5194/tc-12-1957-2018, 2018
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We investigate the relationship between ice wedge polygon topography and near-surface ground temperature using a combination of field work and numerical modeling. We analyze a year-long record of ground temperature across a low-centered polygon, then demonstrate that lower rims and deeper troughs promote warmer conditions in the ice wedge in winter. This finding implies that ice wedge cracking and growth, which are driven by cold conditions, can be impeded by rim erosion or trough subsidence.
Bing Gao, Dawen Yang, Yue Qin, Yuhan Wang, Hongyi Li, Yanlin Zhang, and Tingjun Zhang
The Cryosphere, 12, 657–673, https://doi.org/10.5194/tc-12-657-2018, https://doi.org/10.5194/tc-12-657-2018, 2018
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This study developed a distributed hydrological model coupled with cryospherical processes and applied it in order to simulate the long-term change of frozen ground and its effect on hydrology in the upper Heihe basin. Results showed that the permafrost area shrank by 8.8%, and the frozen depth of seasonally frozen ground decreased. Runoff in cold seasons and annual liquid soil moisture increased due to frozen soils change. Groundwater recharge was enhanced due to the degradation of permafrost.
Youhua Ran, Xin Li, and Guodong Cheng
The Cryosphere, 12, 595–608, https://doi.org/10.5194/tc-12-595-2018, https://doi.org/10.5194/tc-12-595-2018, 2018
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Approximately 88 % of the permafrost area in the 1960s has been thermally degraded in the past half century over the Qinghai–Tibetan Plateau. The mean elevations of the very cold, cold, cool, warm, very warm, and likely thawing permafrost areas increased by 88 m, 97 m, 155 m, 185 m, 161 m, and 250 m, respectively. This degradation may lead to increases in risks to infrastructure, flood, reductions in ecosystem resilience, and positive climate feedback.
Lin Liu and Kristine M. Larson
The Cryosphere, 12, 477–489, https://doi.org/10.5194/tc-12-477-2018, https://doi.org/10.5194/tc-12-477-2018, 2018
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We demonstrate the use of reflected GPS signals to measure elevation changes over a permafrost area in northern Alaska. For the first time, we construct a daily-sampled time series of elevation changes over 12 summers. Our results show regular thaw subsidence within each summer and a secular subsidence trend of 0.3 cm per year. This method promises a new way to utilize GPS data in cold regions for studying frozen ground consistently and sustainably over a long time.
Yonghong Yi, John S. Kimball, Richard H. Chen, Mahta Moghaddam, Rolf H. Reichle, Umakant Mishra, Donatella Zona, and Walter C. Oechel
The Cryosphere, 12, 145–161, https://doi.org/10.5194/tc-12-145-2018, https://doi.org/10.5194/tc-12-145-2018, 2018
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An important feature of the Arctic is large spatial heterogeneity in active layer conditions. We developed a modeling framework integrating airborne longwave radar and satellite data to investigate active layer thickness (ALT) sensitivity to landscape heterogeneity in Alaska. We find uncertainty in spatial and vertical distribution of soil organic carbon is the largest factor affecting ALT accuracy. Advances in remote sensing of soil conditions will enable more accurate ALT predictions.
Benjamin Mewes, Christin Hilbich, Reynald Delaloye, and Christian Hauck
The Cryosphere, 11, 2957–2974, https://doi.org/10.5194/tc-11-2957-2017, https://doi.org/10.5194/tc-11-2957-2017, 2017
Defu Zou, Lin Zhao, Yu Sheng, Ji Chen, Guojie Hu, Tonghua Wu, Jichun Wu, Changwei Xie, Xiaodong Wu, Qiangqiang Pang, Wu Wang, Erji Du, Wangping Li, Guangyue Liu, Jing Li, Yanhui Qin, Yongping Qiao, Zhiwei Wang, Jianzong Shi, and Guodong Cheng
The Cryosphere, 11, 2527–2542, https://doi.org/10.5194/tc-11-2527-2017, https://doi.org/10.5194/tc-11-2527-2017, 2017
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The area and distribution of permafrost on the Tibetan Plateau are unclear and controversial. This paper generated a benchmark map based on the modified remote sensing products and validated it using ground-based data sets. Compared with two existing maps, the new map performed better and showed that permafrost covered areas of 1.06 × 106 km2. The results provide more detailed information on the permafrost distribution and basic data for use in future research on the Tibetan Plateau permafrost.
Jorien E. Vonk, Tommaso Tesi, Lisa Bröder, Henry Holmstrand, Gustaf Hugelius, August Andersson, Oleg Dudarev, Igor Semiletov, and Örjan Gustafsson
The Cryosphere, 11, 1879–1895, https://doi.org/10.5194/tc-11-1879-2017, https://doi.org/10.5194/tc-11-1879-2017, 2017
Florence Magnin, Jean-Yves Josnin, Ludovic Ravanel, Julien Pergaud, Benjamin Pohl, and Philip Deline
The Cryosphere, 11, 1813–1834, https://doi.org/10.5194/tc-11-1813-2017, https://doi.org/10.5194/tc-11-1813-2017, 2017
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Permafrost degradation in high mountain rock walls provokes destabilisation, constituting a threat for human activities. In the Mont Blanc massif, more than 700 rockfalls have been inventoried in recent years (2003, 2007–2015). Understanding permafrost evolution is thus crucial to sustain this densely populated area. This study investigates the changes in rock wall permafrost from 1850 to the recent period and possible optimistic or pessimistic evolutions during the 21st century.
Gonçalo Vieira, Carla Mora, and Ali Faleh
The Cryosphere, 11, 1691–1705, https://doi.org/10.5194/tc-11-1691-2017, https://doi.org/10.5194/tc-11-1691-2017, 2017
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The Toubkal is the highest massif in North Africa (4167 m). Landforms and deposits above 3000 m show the effects of frost action in the present-day geomorphological dynamics, but data on ground temperatures were lacking. In this study ground surface temperature data measured across an altitudinal transect are presented and analysed for the first time. The highlight is the possible occurrence of permafrost at an elevation of 3800 m, which may be of high ecological and hydrological significance.
Sebastian Westermann, Maria Peter, Moritz Langer, Georg Schwamborn, Lutz Schirrmeister, Bernd Etzelmüller, and Julia Boike
The Cryosphere, 11, 1441–1463, https://doi.org/10.5194/tc-11-1441-2017, https://doi.org/10.5194/tc-11-1441-2017, 2017
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We demonstrate a remote-sensing-based scheme estimating the evolution of ground temperature and active layer thickness by means of a ground thermal model. A comparison to in situ observations from the Lena River delta in Siberia indicates that the model is generally capable of reproducing the annual temperature regime and seasonal thawing of the ground. The approach could hence be a first step towards remote detection of ground thermal conditions in permafrost areas.
Gautier Davesne, Daniel Fortier, Florent Domine, and James T. Gray
The Cryosphere, 11, 1351–1370, https://doi.org/10.5194/tc-11-1351-2017, https://doi.org/10.5194/tc-11-1351-2017, 2017
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This study presents data from Mont Jacques-Cartier, the highest summit in the Appalachians of south-eastern Canada, to demonstrate that the occurrence of contemporary permafrost body is associated with a very thin and wind-packed winter snow cover which brings local azonal topo-climatic conditions on the dome-shaped summit. This study is an important preliminary step in modelling the regional spatial distribution of permafrost on the highest summits in eastern North America.
Jonas Wicky and Christian Hauck
The Cryosphere, 11, 1311–1325, https://doi.org/10.5194/tc-11-1311-2017, https://doi.org/10.5194/tc-11-1311-2017, 2017
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Talus slopes are a widespread geomorphic feature, which may show permafrost conditions even at low elevation due to cold microclimates induced by a gravity-driven internal air circulation. We show for the first time a numerical simulation of this internal air circulation of a field-scale talus slope. Results indicate that convective heat transfer leads to a pronounced ground cooling in the lower part of the talus slope favoring the persistence of permafrost.
Graham L. Gilbert, Stefanie Cable, Christine Thiel, Hanne H. Christiansen, and Bo Elberling
The Cryosphere, 11, 1265–1282, https://doi.org/10.5194/tc-11-1265-2017, https://doi.org/10.5194/tc-11-1265-2017, 2017
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We reconstruct the Holocene development of the Zackenberg River delta (northeast Greenland) using a combination of sedimentology, cryostratigraphy, and geochronology. We distinguish four major depositional environments and identify three cryofacies. We apply the principles of cryostratigraphy to infer the aggradational history of permafrost. This paper contains an archive of ground ice in epigenetic permafrost in northeast Greenland.
Xiaoqing Peng, Tingjun Zhang, Oliver W. Frauenfeld, Kang Wang, Bin Cao, Xinyue Zhong, Hang Su, and Cuicui Mu
The Cryosphere, 11, 1059–1073, https://doi.org/10.5194/tc-11-1059-2017, https://doi.org/10.5194/tc-11-1059-2017, 2017
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Previous research has paid significant attention to permafrost, e.g. active layer thickness, soil temperature, area extent, and associated degradation leading to other changes. However, less focus has been given to seasonally frozen ground and vast area extent. We combined data from more than 800 observation stations, as well as gridded data, to investigate soil freeze depth across China. The results indicate that soil freeze depth decreases with climate warming.
Carina Schuh, Andrew Frampton, and Hanne Hvidtfeldt Christiansen
The Cryosphere, 11, 635–651, https://doi.org/10.5194/tc-11-635-2017, https://doi.org/10.5194/tc-11-635-2017, 2017
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This study investigates how soil moisture retention characteristics impact ice and moisture redistribution, heat transport and active layer thickness under permafrost conditions. This is relevant for understanding how climate change interacts with permafrost, which is important because there is much stored carbon in permafrost, which may be released to the atmosphere as permafrost degrades and may then act to further enhance climate warming.
Stephan Gruber, Renate Fleiner, Emilie Guegan, Prajjwal Panday, Marc-Olivier Schmid, Dorothea Stumm, Philippus Wester, Yinsheng Zhang, and Lin Zhao
The Cryosphere, 11, 81–99, https://doi.org/10.5194/tc-11-81-2017, https://doi.org/10.5194/tc-11-81-2017, 2017
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We review what can be inferred about permafrost in the mountains of the Hindu Kush Himalaya region. This is important because the area of permafrost exceeds that of glaciers in this region. Climate change will produce diverse permafrost-related impacts on vegetation, water quality, geohazards, and livelihoods. To mitigate this, a better understanding of high-elevation permafrost in subtropical latitudes as well as the pathways connecting environmental change and human livelihoods, is needed.
Amund F. Borge, Sebastian Westermann, Ingvild Solheim, and Bernd Etzelmüller
The Cryosphere, 11, 1–16, https://doi.org/10.5194/tc-11-1-2017, https://doi.org/10.5194/tc-11-1-2017, 2017
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Palsas and peat plateaus are permafrost landforms in subarctic mires which constitute sensitive ecosystems with strong significance for vegetation, wildlife, hydrology and carbon cycle. We have systematically mapped the occurrence of palsas and peat plateaus in northern Norway by interpretation of aerial images from the 1950s until today. The results show that about half of the area of palsas and peat plateaus has disappeared due to lateral erosion and melting of ground ice in the last 50 years.
Joan Govaerts, Koen Beerten, and Johan ten Veen
The Cryosphere, 10, 2907–2922, https://doi.org/10.5194/tc-10-2907-2016, https://doi.org/10.5194/tc-10-2907-2016, 2016
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The Rupelian Clay in the Netherlands is currently the subject of a feasibility study with respect to the storage of radioactive waste in the Netherlands (OPERA-project). Many features need to be considered in the assessment of the long-term evolution of the natural environment surrounding a geological waste disposal facility. One of these is permafrost development since it may have an impact on various components of the disposal system.
Antoine Marmy, Jan Rajczak, Reynald Delaloye, Christin Hilbich, Martin Hoelzle, Sven Kotlarski, Christophe Lambiel, Jeannette Noetzli, Marcia Phillips, Nadine Salzmann, Benno Staub, and Christian Hauck
The Cryosphere, 10, 2693–2719, https://doi.org/10.5194/tc-10-2693-2016, https://doi.org/10.5194/tc-10-2693-2016, 2016
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This paper presents a new semi-automated method to calibrate the 1-D soil model COUP. It is the first time (as far as we know) that this approach is developed for mountain permafrost. It is applied at six test sites in the Swiss Alps. In a second step, the calibrated model is used for RCM-based simulations with specific downscaling of RCM data to the borehole scale. We show projections of the permafrost evolution at the six sites until the end of the century and according to the A1B scenario.
Benjamin M. Jones, Carson A. Baughman, Vladimir E. Romanovsky, Andrew D. Parsekian, Esther L. Babcock, Eva Stephani, Miriam C. Jones, Guido Grosse, and Edward E. Berg
The Cryosphere, 10, 2673–2692, https://doi.org/10.5194/tc-10-2673-2016, https://doi.org/10.5194/tc-10-2673-2016, 2016
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We combined field data collection with remote sensing data to document the presence and rapid degradation of permafrost in south-central Alaska during 1950–present. Ground temperature measurements confirmed permafrost presence in the region, but remotely sensed images showed that permafrost plateau extent decreased by 60 % since 1950. Better understanding these vulnerable permafrost deposits is important for predicting future permafrost extent across all permafrost regions that are warming.
Jitendra Kumar, Nathan Collier, Gautam Bisht, Richard T. Mills, Peter E. Thornton, Colleen M. Iversen, and Vladimir Romanovsky
The Cryosphere, 10, 2241–2274, https://doi.org/10.5194/tc-10-2241-2016, https://doi.org/10.5194/tc-10-2241-2016, 2016
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Microtopography of the low-gradient polygonal tundra plays a critical role in these ecosystem; however, patterns and drivers are poorly understood. A modeling-based approach was developed in this study to characterize and represent the permafrost soils in the model and simulate the thermal dynamics using a mechanistic high-resolution model. Results shows the ability of the model to simulate the patterns and variability of thermal regimes and improve our understanding of polygonal tundra.
Qingbai Wu, Zhongqiong Zhang, Siru Gao, and Wei Ma
The Cryosphere, 10, 1695–1706, https://doi.org/10.5194/tc-10-1695-2016, https://doi.org/10.5194/tc-10-1695-2016, 2016
Xicai Pan, Yanping Li, Qihao Yu, Xiaogang Shi, Daqing Yang, and Kurt Roth
The Cryosphere, 10, 1591–1603, https://doi.org/10.5194/tc-10-1591-2016, https://doi.org/10.5194/tc-10-1591-2016, 2016
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Using a 9-year dataset in conjunction with a process-based model, we verify that the common assumption of a considerably smaller thermal conductivity in the thawed season than the frozen season is not valid at a site with a stratified active layer on the Qinghai–Tibet Plateau (QTP). The unique hydraulic and thermal mechanism in the active layer challenges the concept of thermal offset used in conceptual permafrost models and hints at the reason for rapid permafrost warming on the QTP.
Pier Paul Overduin, Sebastian Wetterich, Frank Günther, Mikhail N. Grigoriev, Guido Grosse, Lutz Schirrmeister, Hans-Wolfgang Hubberten, and Aleksandr Makarov
The Cryosphere, 10, 1449–1462, https://doi.org/10.5194/tc-10-1449-2016, https://doi.org/10.5194/tc-10-1449-2016, 2016
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How fast does permafrost warm up and thaw after it is covered by the sea? Ice-rich permafrost in the Laptev Sea, Siberia, is rapidly eroded by warm air and waves. We used a floating electrical technique to measure the depth of permafrost thaw below the sea, and compared it to 60 years of coastline retreat and permafrost depths from drilling 30 years ago. Thaw is rapid right after flooding of the land and slows over time. The depth of permafrost is related to how fast the coast retreats.
W. Wang, A. Rinke, J. C. Moore, X. Cui, D. Ji, Q. Li, N. Zhang, C. Wang, S. Zhang, D. M. Lawrence, A. D. McGuire, W. Zhang, C. Delire, C. Koven, K. Saito, A. MacDougall, E. Burke, and B. Decharme
The Cryosphere, 10, 287–306, https://doi.org/10.5194/tc-10-287-2016, https://doi.org/10.5194/tc-10-287-2016, 2016
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We use a model-ensemble approach for simulating permafrost on the Tibetan Plateau. We identify the uncertainties across models (state-of-the-art land surface models) and across methods (most commonly used methods to define permafrost).
We differentiate between uncertainties stemming from climatic driving data or from physical process parameterization, and show how these uncertainties vary seasonally and inter-annually, and how estimates are subject to the definition of permafrost used.
We differentiate between uncertainties stemming from climatic driving data or from physical process parameterization, and show how these uncertainties vary seasonally and inter-annually, and how estimates are subject to the definition of permafrost used.
S. Peng, P. Ciais, G. Krinner, T. Wang, I. Gouttevin, A. D. McGuire, D. Lawrence, E. Burke, X. Chen, B. Decharme, C. Koven, A. MacDougall, A. Rinke, K. Saito, W. Zhang, R. Alkama, T. J. Bohn, C. Delire, T. Hajima, D. Ji, D. P. Lettenmaier, P. A. Miller, J. C. Moore, B. Smith, and T. Sueyoshi
The Cryosphere, 10, 179–192, https://doi.org/10.5194/tc-10-179-2016, https://doi.org/10.5194/tc-10-179-2016, 2016
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Soil temperature change is a key indicator of the dynamics of permafrost. Using nine process-based ecosystem models with permafrost processes, a large spread of soil temperature trends across the models. Air temperature and longwave downward radiation are the main drivers of soil temperature trends. Based on an emerging observation constraint method, the total boreal near-surface permafrost area decrease comprised between 39 ± 14 × 103 and 75 ± 14 × 103 km2 yr−1 from 1960 to 2000.
Cited articles
ACGR: Glossary of permafrost and related ground ice terms, Associate Committee on Geotechnical Research (ACGR), National Research Council of Canada, Ottawa, 1988.
Anisimov, O. A., Lobanov, V. A., Reneva, S. A., Shiklomanov, N. I., Zhang, T., and Nelson, F. E.: Uncertainties in gridded air temperature fields and effects on predictive active layer modeling, J. Geophys. Res., 112, F02S14, https://doi.org/10.1029/2006JF000593, 2007.
Balk, D., Pozzi, F., Yetman, G., Deichmann, U., and Nelson, A.: The distribution of people and the dimension of place: methodologies to improve the global estimation of urban extents, in: International Society for Photogrammetry and Remote Sensing, Proceedings of the Urban Remote Sensing Conference, 14-–16 March 2005, Tempe, Arizona, US, 2005.
Baranov, I. J. and Kudryavtsev, V. A.: Permafrost of Eurasia, in: Proceedings Permafrost International Conference, Nat. Acad. Sei.-Nat. Res. Council, Publ, 11–-15 November 1963, Lafayette, Indianna, US, 1287, 99–102, 1963.
Bockheim, J. G.: Permafrost distribution in the southern circumpolar region and its relation to the environment: a review and recommendations for further research, Permafrost Periglac., 6, 27–45, 1995.
Boike, J., Wille, C., and Abnizova, A.: Climatology and summer energy and water balance of polygonal tundra in the Lena River Delta, Siberia, J. Geophys. Res., 113, G03025, https://doi.org/10.1029/2007JG000540, 2008.
Bommer, C., Phillips, M., and Arenson, L. U.: Practical recommendations for planning, constructing and maintaining infrastructure in mountain permafrost, Permafrost Periglac., 21, 97–104, 2010.
Bowden, W. B., Gooseff, M. N., Balser, A., Green, A., Peterson, B. J., and Bradford, J.: Sediment and nutrient delivery from thermokarst features in the foothills of the North Slope, Alaska: potential impacts on headwater stream ecosystems, J. Geophys. Res., 113, G02026, https://doi.org/10.1029/2007JG000470, 2008.
Brown, J., Ferrians Jr, O. J., Heginbottom, J. A., and Melnikov, E. S.: Circum-Arctic map of permafrost and ground-ice conditions, Washington, DC: U.S. Geological Survey in Cooperation with the Circum-Pacific Council for Energy and Mineral Resources, Circum-Pacific Map Series CP-45, scale 1:10,000,000, 1 sheet, 1997.
Brown, R. J. E. and Pewe, T. L.: Distribution of permafrost in North America and its relationship to the environment: a review, in: Permafrost: North American Contribution, Second International Conference, 71–100, 1973.
Burn, C. R.: Lake-bottom thermal regimes, western Arctic coast, Canada, Permafrost Periglac., 16, 355–367, https://doi.org/10.1002/ppp.542, 2005.
Cremonese, E., Gruber, S., Phillips, M., Pogliotti, P., Boeckli, L., Noetzli, J., Suter, C., Bodin, X., Crepaz, A., Kellerer-Pirklbauer, A., Lang, K., Letey, S., Mair, V., Morra di Cella, U., Ravanel, L., Scapozza, C., Seppi, R., and Zischg, A.: Brief Communication: "An inventory of permafrost evidence for the European Alps", The Cryosphere, 5, 651–657, https://doi.org/10.5194/tc-5-651-2011, 2011.
Defense Mapping Agency: Digital Chart of the World, Tech. rep., Defense Mapping Agency (DMA), Fairfax, Virginia, 1992.
Delaloye, R., Reynard, E., Lambiel, C., Marescot, L., and Monnet, R.: Thermal anomaly in a cold scree slope (Creux du Van, Switzerland), in: Proceedings of the 8th International Conference on Permafrost, 21–25 July, 2003, Zürich, Switzerland, Balkema Publishers, Lisse, The Netherlands, 175–180, 2003.
Endrizzi, S., Quinton, W. L., and Marsh, P.: Modelling the spatial pattern of ground thaw in a small basin in the arctic tundra, The Cryosphere Discuss., 5, 367–400, https://doi.org/10.5194/tcd-5-367-2011, 2011.
ESRI: Data and Maps 10, white paper, Tech. rep., ESRI, 380 New York St., Redlands, CA 92373-8100 USA, 2010.
Farr, T. G., Rosen, P. A., Caro, E., Crippen, R., Duren, R., Hensley, S., Kobrick, M., Paller, M., Rodriguez, E., Roth, L., Seal, D., Shaffer, S., Shimada, J., Umland, J., Werner, M., Oskin, M., Burbank, D., and Alsdorf, D.: The shuttle radar topography mission, Rev. Geophys., 45, RG2004, 33 pp., 2007.
Giorgi, F. and Avissar, R.: Representation of heterogeneity effects in Earth system modeling: Experience from land surface modeling, Rev. Geophys., 35, 413–437, 1997.
Gooseff, M. N., Balser, A., Bowden, W. B., and Jones, J. B.: Effects of hillslope thermokarst in northern Alaska, EOS T. Am. Geophys. Un., 90, 29–30, 2009.
Gruber, S. and Haeberli, W.: Permafrost in steep bedrock slopes and its temperature-related destabilization following climate change, J. Geophys. Res., 112, F02S18, https://doi.org/10.1029/2006JF000547, 2007.
Gubler, S., Fiddes, J., Keller, M., and Gruber, S.: Scale-dependent measurement and analysis of ground surface temperature variability in alpine terrain, The Cryosphere, 5, 431–443, https://doi.org/10.5194/tc-5-431-2011, 2011.
Harris, C., Arenson, L. U., Christiansen, H. H., Etzelmüller, B., Frauenfelder, R., Gruber, S., Haeberli, W., Hauck, C., Hölzle, M., Humlum, O., Isaksen, K., Kääb, A., Kern-Lütschg, M. A., Lehning, M., Matsuoka, N., Murton, J. B., Nötzli, J., Phillips, M., Ross, N., Seppälä, M., Springman, S. M., and Mühll, D. V.: Permafrost and climate in Europe: Monitoring and modelling thermal, geomorphological and geotechnical responses, Earth-Sci. Rev., 92, 117–171, https://doi.org/10.1016/j.earscirev.2008.12.002, 2009.
Heginbottom, J. A.: Permafrost mapping: a review, Prog. Phys. Geog., 26, 623–642, 2002.
Heginbottom, J. A. and Dubreuil, M. A.: A new permafrost and ground ice map for the national atlas of Canada, in: Proceedings of the Sixth International Conference on Permafrost, 5–9 July, 1993, Beijing, China, 255–260, 1993.
Jorgenson, M. T., Racine, C. H., Walters, J. C., and Osterkamp, T. E.: Permafrost degradation and ecological changes associated with a warming climate in Central Alaska, Climatic Change, 48, 551–579, 2001.
Jorgenson, M. T., Shur, Y. L., and Pullman, E. R.: Abrupt increase in permafrost degradation in Arctic Alaska, Geophys. Res. Lett., 33, L02503, https://doi.org/10.1029/2005GL024960, 2006.
Kalnay, E. C., Kanamitsu, M., Kistler, R., Collins, W., Deaven, D., Gandin, L., Iredell, M., Saha, S., White, G., Woollen, J., Zhu, Y., Leetmaa, A., Reynolds, R., Chelliah, M., Ebisuzaki, W., Higgins, W., Janowiak, J., Mo, K. C., Ropelewski, C., Wang, J., Jenne, R., and Joseph, D.: The NCEP/NCAR 40-year reanalysis project, B. Am. Meteorol. Soc., 77, 437–471, 1996.
King, L.: Zonation and ecology of high mountain permafrost in Scandinavia, Geogr. Ann. A, 68, 131–139, 1986.
Langer, M., Westermann, S., Muster, S., Piel, K., and Boike, J.: The surface energy balance of a polygonal tundra site in northern Siberia – Part 1: Spring to fall, The Cryosphere, 5, 151–171, https://doi.org/10.5194/tc-5-151-2011, 2011.
Larsen, P. H., Goldsmith, S., Smith, O., Wilson, M. L., Strzepek, K., Chinowsky, P., and Saylor, B.: Estimating future costs for Alaska public infrastructure at risk from climate change, Global Environ. Chang., 18, 442–457, 2008.
Lewkowicz, A. G. and Harris, C.: Morphology and geotechnique of active-layer detachment failures in discontinuous and continuous permafrost, Northern Canada, Geomorphology, 69, 275–297, 2005.
Lewkowicz, A. G. and Bonnaventure, P. P.: Interchangeability of mountain permafrost probability models, Northwest Canada, Permafrost Periglac., 19, 49–62, 2008.
Liston, G. E.: Representing subgrid snow cover heterogeneities in regional and global models, J. Climate, 17, 1381–1397, 2004.
Ma, L., Zhang, T., Li, Q., Frauenfeld, O., and Qin, D.: Evaluation of ERA-40, NCEP-1, and NCEP-2 reanalysis air temperatures with ground-based measurements in China, J. Geophys. Res., 113, D15115, https://doi.org/10.1029/2007JD009549, 2008.
Melton, M. A.: The geomorphic and paleoclimatic significance of alluvial deposits in Southern Arizona, J. Geol., 73, 1–38, 1965.
Mitchell, T. D., Carter, T. R., Jones, P. D., Hulme, M., and New, M.: A comprehensive set of high-resolution grids of monthly climate for Europe and the globe: the observed record (1901–2000) and 16 scenarios (2001–2100), Tyndall Centre for Climate Change Research Working Paper, 55, 25, 2004.
Mokhov, I. I. and Akperov, M. G.: Tropospheric lapse rate and its relation to surface temperature from reanalysis data, Izv. Atmos. Ocean. Phy., 42, 430–438, 2006.
Nelson, F. E. and Outcalt, S. I.: A computational method for prediction and regionalization of permafrost, Arctic Alpine Res., 19, 279–288, https://doi.org/10.2307/1551363, 1987.
Nelson, F. E., Shiklomanov, N. I., Mueller, G. R., Hinkel, K. M., Walker, D. A., and Bockheim, J. G.: Estimating active-layer thickness over a large region: Kuparuk River Basin, Alaska, USA, Arctic Alpine Res., 29, 367–378, https://doi.org/10.2307/1551985, 1997.
Nelson, F. E., Anisimov, O. A., and Shiklomanov, N. I.: Subsidence risk from thawing permafrost, Nature, 410, 889–890, 2001.
Nelson, F. E., Anisimov, O. A., and Shiklomanov, N. I.: Climate change and hazard zonation in the circum-Arctic permafrost regions, Nat. Hazards, 26, 203–225, 2002.
Nikiforoff, C.: The perpetually frozen subsoil of Siberia, Soil Sci., 26, 61, 1928.
Osterkamp, T. E.: Sub-sea permafrost, in: Encyclopedia of Ocean Sciences, edited by: Steele, J. H., Thorpe, S. A., and Turekian, K. K., 2902–2912, 2001.
Peng, C., Ouyang, H., Gao, Q., Jiang, Y., Zhang, F., Li, J., and Yu, Q.: Building a "green" railway in China, Science, 316, 546–547, https://doi.org/10.1126/science.1134134, 2007.
Péwé, T. L.: Alpine permafrost in the contiguous United States: a review, Arctic Alpine Res., 15, 145–156, 1983.
Raup, B., Racoviteanu, A., Khalsa, S. J., Helm, C., Armstrong, R., and Arnaud, Y.: The GLIMS geospatial glacier database: a new tool for studying glacier change, Global Planet. Change, 56, 101–110, 2007.
Riseborough, D., Shiklomanov, N., Etzelm{ü}ller, B., Gruber, S., and Marchenko, S.: Recent advances in permafrost modelling, Permafrost Periglac., 19, 137–156, 2008.
Romanovsky, V., Gruber, S., Instanes, A., Jin, H., Marchenko, S., Smith, S., Trombotto, D., and Walter, K.: Global Outlook for Ice and Snow, chap. 7: Frozen ground, United Nations Environment Programme, Nairobi, Kenya, 2007.
Rykiel, E. J.: Testing ecological models: the meaning of validation, Ecol. Model., 90, 229–244, 1996.
Shakhova, N., Semiletov, I., Salyuk, A., Yusupov, V., Kosmach, D., and Gustafsson, O.: Extensive Methane Venting to the Atmosphere from Sediments of the East Siberian Arctic Shelf, Science, 327, 1246–1250, https://doi.org/10.1126/science.1182221, 2010.
Shur, Y. L. and Jorgenson, M. T.: Patterns of permafrost formation and degradation in relation to climate and ecosystems, Permafrost Periglac., 18, 7–19, https://doi.org/10.1002/ppp.582, 2007.
Smith, M. W. and Riseborough, D. W.: Climate and the limits of permafrost: a zonal analysis, Permafrost Periglac., 13, 1–15, 2002.
Stendel, M. and Christensen, J. H.: Impact of global warming on permafrost conditions in a coupled GCM, Geophys. Res. Lett., 29, 1632, 2002.
Sturm, M. and Benson, C.: Scales of spatial heterogeneity for perennial and seasonal snow layers, Ann. Glaciol., 38, 253–260, https://doi.org/10.3189/172756404781815112, 2004.
USGS: Global 30 Arc-Second Elevation Data Set GTOPO30, United States Geological Survey Earth Resources Observation and Science Center, available at: http://eros.usgs.gov/#/{\breakFind{_}Data/Products{_}and{_}Data{_}Available/gtopo30{_}info}, 2004.
USGS: SRTM30 Documentation, United States Geological Survey Earth Resources Observation and Science Center, available at: http://dds.cr.usgs.gov/srtm/version2{_1/{\break}SRTM30/srtm30{_}documentation.pdf}, 2005.
Vincent, L. A., Zhang, X., Bonsal, B. R., and Hogg, W. D.: Homogenization of daily temperatures over Canada, J. Climate, 15, 1322–1334, 2002.
Walter, K. M., Zimov, S. A., Chanton, J. P., Verbyla, D., and Chapin, F. S.: Methane bubbling from Siberian thaw lakes as a positive feedback to climate warming, Nature, 443, 71–75, 2006.
Wang, B. and French, H. M.: Permafrost on the Tibet Plateau, China, Quaternary Sci. Rev., 14, 255–274, https://doi.org/10.1016/0277-3791(95)00006-B, 1995.
Wang, G., Li, Y., Wu, Q., and Wang, Y.: Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau, Sci. China Ser. D, 49, 1156–1169, 2006.
Williams, P. J. and Smith, M. W.: The Frozen Earth, Cambridge University Press, Cambridge University Press, Cambridge, UK, 1989.
Woo, M. K., Kane, D. L., Carey, S. K., and Yang, D.: Progress in permafrost hydrology in the new millennium, Permafrost Periglac., 19, 237–254, 2008.
Wright, J. F., Duchesne, C., and Côté, M. M.: Regional-scale permafrost mapping using the TTOP ground temperature model, in: Proceedings 8th International Conference on Permafrost, Swets and Zeitlinger, Lisse, 1241–1246, 2003.
Zhang, T.: Influence of the seasonal snow cover on the ground thermal regime: an overview, Rev. Geophys., 43, RG4002, 23 pp., https://doi.org/10.1029/2004RG000157, 2005.
Zhang, T., Barry, R. G., Knowles, K., Heginbottom, J. A., and Brown, J.: Statistics and characteristics of permafrost and ground-ice distribution in the Northern Hemisphere, Polar Geogr., 23, 132–154, 1999.
Zhang, T., Heginbottom, J. A., Barry, R. G., and Brown, J.: Further statistics on the distribution of permafrost and ground ice in the Northern Hemisphere, Polar Geogr., 24, 126–131, 2000.
